(上海交通大學(xué) 材料科學(xué)與工程學(xué)院，上海 200030)
摘 要: 研究了一種含有稀土化合物的鋁合金新型熔劑JDN-I。結(jié)果表明，該熔劑通過發(fā)生一系列的物理和化學(xué)反應(yīng)，不僅可使A356合金熔體720 ℃時(shí)的含氫量由大于0.30 mL/100 g(Al)下降到0.10 mL/100 g(Al)以下，除氣效果顯著，并使A356合金的室溫抗拉強(qiáng)度提高7.27%，延伸率提高85.58%。該熔劑還具有細(xì)化晶粒和變質(zhì)的作用，分析了該熔劑發(fā)生作用的機(jī)理，提出了有效稀土量和臨界有效稀土量的概念。
關(guān)鍵字: 鋁合金； 稀土熔劑； 除氫除雜； 有效稀土量； 臨界有效稀土量
（College of Materials Science and Engineering，
Shanghai Jiaotong University， Shanghai 200030，P.R.China）
Abstract: A new flux—JDN-I including rare earth compounds for aluminium and its alloys was introduced. With complex physical and chemical effect， function of degassing， drossing， covering， refining and modification was excellent. The hydrogen content could be decreased greatly with JDN-I in A356 aluminium meltfrom >0.30 mL/100 g(Al) to <0.10 mL/100 g(Al),σb be increased by 7.27% and δ be increased by 85.5%. At the meantime， with JDN-I the mechanical properties of A356 could be increased. The mechanism of JDN-I improving properties and microstructure was discussed. The concepts of effective rare earth quantity and critically effective rare earth quantity were proposed also.
Key words: aluminum alloys; rare earth flux; degassing hydrogen and drossing; effective rare earth quantity; critically effective rare earth quantity
